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<head>
    <meta charset="UTF-8">
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    <title>Document</title>
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<body>
    <script>
        // undefined
        //var x;
        //alert(x)
        //字符
        var str1="hello word";
        var str2="hello word";
        console.log(str1)
        console.log(str2)
        //var str3="hello word"
        var str4 = '灰太狼说:"小红很漂亮"';
        console.log(str4);
        var str ="Java"
        //JS中先运算等号右边的语句
        str =str +"Script";//字符串中+号是连续的意思 JavaScript
        console.log(str);
    </script>
</body>
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